X. To protect their natural habitats d. To domesticate them -11 . Which of the following is a noun group? __ a. Running fast b. The big brown dog c.Quickly and quietly d. Quickly and quietly

b. The big brown dogA noun group (or noun phrase) includes a noun and all the words that modify it. "The big brown dog" fits this definition as it centers around the noun "dog" with modifiers "the," "big," and "brown."